What it is and what the ratings mean
The Siemens SENTRON 5SY4313-8CC is a 3-pole miniature circuit breaker rated 13 A with a D tripping characteristic, breaking 10 kA at 400 V AC per IEC 60898. That D curve means it tolerates high inrush currents — think motor starting, transformer energization, or welding equipment — without nuisance tripping on the magnetic trip. The 10 kA SCCR at 400 V tells you it safely interrupts a fault up to that level without welding contacts or cascading upstream. It occupies 3 modular-width units (54 mm) on a DIN rail, mounts in any position, and accepts supplementary devices (auxiliary contacts, shunt trips, alarm switches) via the integrated accessory slot. The IP20 rating applies only with connected conductors — fine inside an enclosed panel, not for wet or dusty locations.
Panel fit and environmental limits
Depth is 76 mm, height 90 mm, width 54 mm — fits a standard 3-MW DIN-rail footprint. Installation depth is 70 mm, so plan for 6 mm of busbar or wire clearance behind the rail. Ambient range runs from -40 °C to 75 °C, with humidity derating above 55 °C: 95% RH at 55 °C, 55% at 70 °C, 35% at 75 °C. Vibration resistance per IEC 60068-2-6: ±1 mm at 5–25 Hz, 50 m/s² at 25–150 Hz.